Treating severe drug-induced hyperthermia with an ice-water bath

February 20, 2015, 7:23 pm

Ice Bath★★★☆☆

Ice water submersion for rapid cooling in severe drug-induced hyperthermia. Laskowski LK et al. Clin Toxicol 2015 Mar;53:181-184.


There is still debate about the optimal method of cooling severely hyperthermic patients, such as those with core temperature > 104oF (40oC) who are exhibiting changes in mental status. Some common techniques include ice packs to the groin and axillae, cooling blankets, along with convection (evaporation) techniques such as cool sprays and fans. There is little debate, however, about the proposition that the faster these extremely hyperthermic patients are cooled the better the outcomes.

This fascinating paper present 2 spectacular cases of drug-induced severe hyperthermia treated by submerging the patient in an ice-water bath:

  1. A 27-year-old man was brought to the hospital with agitation after ingesting 4-fluoroamphetamine. (This was confirmed in the laboratory.) His rectal temperature was 106.5oF (41.4oC). He was immediately placed in an ice water bath, with core temperature measured every 5-60 seconds. After 22 minutes in the bath, he core temperature was 99.3oF (37.4oC). The patient received a total dose of 28 mg midazolam while submerged and did not exhibit shivering. On the second hospital day, he signed out against medical advice.
  2. A 32-year-old man was brought to hospital because of agitation and hallucinations after using cocaine. His rectal temperature was 112oF (44,4oC)!! He was paralyzed, intubated, and place in an ice-water bath. After 20 minutes in the bath, his core temperature was 102oF (38.8oC.) He was discharged after 10 days in hospital”in stable condition,” although no mention is made of his mental status.

These temperatures are impressive, especially in the second case. (I think 112oF is hot enough to sous vide a salmon.) In the discussion section, the authors describe their technique:

The steps to performing ice water submersion are straight-forward. Once hyperthermia is documented, the patient should be immediately undressed, wrapped in a sheet, and place in a water-impermeable bed (when available), while indirect patient care staff fill large plastic bags with ice to cover and surround the patient. Important nursing and patient care technician roles include establishment of IV access, administration of medication, and placement of cardiac leads, pulse oximetry and a rectal probe for continual core temperature monitoring. Benzodiazepines may be indicated to treat psychomotor agitation. Rapid sequence incubation and advanced cardiac life support measures, if indicated, can and should be performed with the patient in the ice bath. While a lack of evidence exists to guide a specific endpoint temperature, we recommend at endpoint core temperature of 39oC (102.2oF), at which point the patient should be moved to a new hospital bed and dried completely, to avoid an overshoot towards hypothermia.

In an editorial commentary piece, Dr. Edward Otten from the University of Cincinnati states that although defibrillation would be difficult to perform on a patient in an ice-water bath, significant cardiac arrhythmias are rare in hyperthermia. He also suggests that an esophageal thermometer might be a preferred method of measuring core temperature, since it does not come into contact with ice water.

This is a case series of only 2 patients, but very interesting and worth reading.


  1. Andrew Says:

    For comparison, NCBI has a case ( where “the application of ice packs to the groin and axillae and a cooling blanket” managed to lower a patient’s temperature by about 12°F (from 113°F to 100.6°F) in 100 minutes.

    The paper associates the amazingly good outcome of this particular patient (no renal failure or DIC and no neurological deficits) to, amongst other factors, “aggressive initial IV hydration”.

  2. anon Says:

    Rapid series incubation?

  3. Leon Says:


    Thank you for referencing the case reported by jeff Suchard. The rate of cooling in that case was 0.07 C/min. The rates in the 2 cases presented by Laskowski et al was 0.18 C/min and 0.28 C/min. Suchard’s case did well. Certainly ice-water immersion will bring down the extremely high body temperature faster, which is theoretically an advantage. Of course, not all facilities are set up to accomplish it, and there is not enough data to determine if the faster rate of cooling is crucial, or offers benefits that offset any adverse effects. We will certainly never get a good randomized trial. I think the key thing in these patients is to recognize hyperthermia early on and institute the most aggressive cooling techniques available and feasible. Certainly, rehydration is also key.

    Anon: I sometimes mis-type “incubation” when I mean “intubation.” However, i do not believe I did so in this review.

  4. Rosalind Says:

    Something I have seen dramatically reverse severe hyperthermia in dogs is to establish a rapidly-flowing IV line and then place a couple of loops of the line in a bowl of ice water. Perhaps this might be helpful in human situations where a lot of ice, or a bath-sized receptacle for the patient, is not available, because only moderate amounts of ice, and a medium-sized bowl, are required.
    Since you are advocating rapid rehydration in any case, chilling of the fluid on the way in seems like a simple addition.